Rolling element bearing having separate lubricant feeds for rolling elements and antechamber

ABSTRACT

The invention pertains to a rolling element bearing for a product conveyor and/or product processing element of a harvesting machine, with the bearing including a rolling element chamber and an antechamber, that protects the rolling elements from the penetration of plant juices. A first lubricant feed is provided for supplying lubricant to the rolling elements and a separate second lubricant feed is provided for supplying lubricant to the antechamber.

FIELD OF THE INVENTION

[0001] The present invention relates to rolling element bearings, andmore particularly relates to a seal and lubricating arrangement for suchbearings.

BACKGROUND OF THE INVENTION

[0002] A conveyor roller of a field chopper is described in document DD121 704 in which several grease chambers are located in front of abearing in the direction of the conveyor roller, with the bearing beingin the form of an adjusting-ring bearing. The grease chambers are usedto protect the adjusting-ring bearing against penetration of plantjuices that can cause corrosion and destruction of the adjusting-ringbearing. The single grease feed is connected with the central lubricantfeed and supplies the adjusting ring bearing with grease that also movesfrom the adjusting-ring bearing through seals into the grease chamber.In this regard, it is considered to be a disadvantage that theadjusting-ring bearing has to be supplied with a relatively highlubricant pressure so that the grease chamber will be supplied withenough grease. Thus, high grease consumption will result, and theadjusting-ring bearing can be damaged by excessive grease pressure orexcessive lubricant.

SUMMARY OF THE INVENTION

[0003] According to the present invention, there is provided an improvedbearing arrangement for use in a corrosive environment such as that ofproduct conveying and/or product processing elements of a cropharvesting machine.

[0004] A primary object of the invention is to provide a rolling elementbearing constructed such that satisfactory lubrication of theantechamber is possible without excessive lubrication of the rollingelements.

[0005] A more specific object of the invention is to provide an improvedrolling element bearing having an antechamber protecting the rollingelements against penetration of corrosive fluid, such as plant juices,wherein the antechamber is connected with a first lubricant feed, andthe chamber containing the rolling elements is connected with a secondlubricant feed. In this manner, the antechamber and the rollingelements, which may be ball bearings, tapered roller bearings or needlebearings, can be separately supplied with lubricant (usually grease). Itwould also be possible to use sliding bearing elements instead of therolling bearing elements.

[0006] Another object of the invention is to provide a rolling bearing,as set forth in one or more previous objects, wherein the antechamber isconnected to the first lubricant feed via a first duct, while thechamber containing the rolling elements is connected to the secondlubricant feed via a second duct having no direct connection with thefirst duct.

[0007] These and other objects of the invention will become apparentfrom a reading of the ensuing description together with the appendeddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008]FIG. 1 is a schematic, left side elevational view of a harvestingmachine that is representative of the machines with which the presentinvention is particularly adapted for use.

[0009]FIG. 2 is a cross section of a bearing constructed according tothe present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0010] A harvesting machine 10, shown in FIG. 1, as a kind ofself-propelled field chopper, is constructed on a chassis 12 that issupported by front and rear pairs of wheels 14 and 16. Operation of theharvesting machine 10 is done from the operator's cab 18, where a croppickup device 20, in the form of a corn harvester, is visible. By usingthe crop pickup device 20, the product picked up from the ground, e.g.,corn, grass or the like, is sent to a chopper drum 22 that chops it intosmall pieces and moves it to a conveyor device 24. The product leavesthe harvesting machine 10 and passes by means of a rotatable deliverychute 26 to a trailer moving alongside. Between the chopper drum 22 andthe conveyor device 24 there is a kernel processor or after-crusherdevice 28 by means of which the product to be conveyed is suppliedtangentially to the conveyor device 24. The after-crusher device 28 haslower and upper rollers 30 and 32, respectively, which are rotating inmutually opposing directions.

[0011] One potential problem of the after-crusher device 28 and also ofthe other product conveyor and/or product processing elements of theharvesting machine 10, for example, the conveyor device 24 and theintake rollers (not shown) that are located ahead of, and deliver a cropmat to, the chopper drum 22, is that during conveyance or processing ofthe crop, plant juices are produced that get into the bearings of theproduct conveyor and/or product processing elements and can destroy themdue to corrosion.

[0012] In order to prevent the penetration of plant juices into thebearing rollers, opposite ends of the lower roller 30 of theafter-crusher device 28 are each equipped with a bearing 34 that isillustrated in detail in FIG. 2. Also, the upper roller 32 can beequipped with a bearing 34 of this kind.

[0013] The roller 30 features a hollow cylindrical casing 38 into whichan end support ring 40 is inserted. The support ring 40 supports a stubshaft 36. Between the support ring 40 and the bearing 34 there is asupport ring 42 arranged on the stub shaft 36 that is intended toprotect the bearing 34 from plant juices. The bearing 34 features aninner ball race 44 that is seated on the stub shaft 36, and an outerball race 46 that surrounds the inner ball race 44. Between the innerball race 44 and the outer ball race 46 are two rows of balls 48designed as rolling bearings, with each row of balls being held in acage 50 and roll in corresponding, opposed sets of axially spaced,curved rolling tracks. The inner ball race 44 is secured to the stubshaft 36 by a clamping ring 52. The clamping ring 52, or the part of thestub shaft 36 extending out beyond it to the right in the figure, canalso be used for attachment of a belt pulley or of another kind of drivedevice. The outer ball race 46 is surrounded radially by a bearinghousing 54, which in turn is attached to a side wall 56 of the productconveyor duct of the harvesting machine 10.

[0014] Between the bearing housing 54 and the inner ball race 44 thereis a first seal 58, in the form of a ring that is connected to thebearing housing 54 and extends radially inward almost to the exterior ofthe inner ball race 44. A second seal 60 in the form of a ring extendingradially outward from the inner ball race 44, whose outer region curvesaxially away from the roller 30, is spaced axially outward farther fromthe roller than the first seal 58. The first seal 58 and the second seal60 form a labyrinth seal. A third seal 62 with flexible lips 62 restingagainst the inner ball race 44 in turn is farther from the roller 30than the second seal 60 and is joined to the outer ball race 46. Thethree seals 58, 60, 62 prevent plant juices from reaching the bearingballs 48. On the opposite side of the bearing 34 from the roller 30,there are three additional seals 64, 66, 68 that are essentiallysymmetrical with the three seals 58, 60, 62. The outer seal 68, however,is located opposite the clamping ring 52.

[0015] Between the first seal 58, the second seal 60 and the third seal62 there is an annular antechamber 70 that is supplied with grease via afirst lubricant feed 72 that is coupled to the antechamber 70 by a duct74 passing radially through the bearing housing 54. The balls 48 aresupplied with grease via a second lubricant feed 76 coupled to a duct 78passing radially through the bearing housing 54. Also, an annular outerantechamber 80 between the three seals 64, 66 and 68 is supplied withgrease via the second duct 78, passing through the space between theballs 48 and under the flexible lips of the outer seal 64. The separatelubricant feeds 72 and 76 make it possible to supply the antechamber 70and the balls 48 with grease separately, so that the supplied quantitiesof grease can be measured out according to the particular requirements.The amount of grease can be specified by means of the time intervalbetween lubrications, or by the particular amount of grease supplied.Thus, the antechamber 70 can be supplied with a relatively large amountof grease to compensate for the spent, old grease that is forced out ofthe antechamber 70 along with the plant juices, whereas the balls 48receive relatively little grease and at a lower pressure, which willextend their service life. The lubricant feeds 72, 76 are preferablyconnected with a central lubricant supply 82 of the harvesting machine10.

[0016] It should be mentioned also that the outer antechamber 80 couldbe supplied with grease from an associated third lubricant feed and acorresponding separate duct. The lubricant feeds 72 and 76 need not belocated diametrically opposite each other, as shown in the figure, butrather can be angularly offset from each other by just a few degrees.

[0017] Having described the preferred embodiment, it will becomeapparent that various modifications can be made without departing fromthe scope of the invention as defined in the accompanying claims.

1. A rolling element bearing adapted for use in rotatably supporting ashaft of a crop product conveyor or processing element, comprising: aninner race; an outer race; a housing containing said outer race; saidinner and outer races cooperating to define a rolling element chamberbetween them; rolling elements located in said rolling element chamber;a first pair of seal members being respectively located adjacent axiallyopposite ends of said outer race and extending to said inner race so asto enclose said rolling element chamber; a second pair of seal membersrespectively located adjacent opposite ends of said housing in axiallyspaced relationship to said first pair of seal members; said second pairof seal members extending between said housing and said inner race andcooperating with said first pair of seal members to define first andsecond antechambers; a first lubricant feed device being connected influid communication with one of said first and second antechambers, anda second lubricant feed device being connected in fluid communicationwith said rolling element chamber, whereby lubricant may beindependently supplied to said one of said first and second antechambersand to said rolling element chamber.
 2. The bearing, as defined in claim1, wherein said first and second lubricant feed devices are not indirect fluid communication with each other.
 3. The bearing, as definedin claim 1, wherein said first pair of seal members include flexibleradially inner lips engaged with said inner race, with the respectivelips of the pair of seals being flexed axially away from each other,whereby lubricant may pass from said rolling element chamber to anotherof said first and second antechambers.